Test on Unit 4 - University City Schools

Name: ______________________ Class: _________________ Date: _________ID: ADNA and Gene Expression (chaps 12-14)Multiple ChoiceIdentify the choice that best completes the statement or answers the question.____1 The enzyme peptidyl transferase, which catalyzes the transfer of the polypeptide chain attached tothe tRNA in the __________ site to the aminoacyl-tRNA in the __________ site, is thought to bea(n) __________ molecule and not a protein.A. A; P; rDNAB. P; A; tRNAC. P; A; sugarD. A; P; mRNAE. P; A; rRNAFigure 12-2Use the figure to answer the corresponding question(s).________2 Refer to Figure 12-2. The enzyme represented by the letter D is responsible for:A. synthesizing the leading strand.B. forming the replication fork.C. unwinding the DNA double helix.D. linking short DNA segments.E. forming nucleosomes.3 Refer to Figure 12-2. The correct designation for the DNA strand labeled C is:A. polymerase.B. the leading strand.C. 3′.D. Okazaki fragments.E. None of these.1

Name: ______________________ID: A________________4 Refer to Figure 12-2. The segments labeled F are responsible for:A. unwinding the DNA double helix.B. linking short DNA segments.C. forming the replication fork.D. synthesizing the leading strand.E. initiating DNA synthesis.5 Refer to Figure 12-2. The structures represented by the letter E are called:A. DNA polymerases.B. Okazaki fragments.C. nucleosomes.D. replication forks.E. leading fragments6 Uracil forms a complementary pair with __________ in RNA and __________ in DNA.A. uracil; adenineB. adenine; adenineC. thymine; thymineD. adenine; thymineE. adenine; uracil7 The tRNA:A. must have an anticodon.B. must be recognized by ribosomes.C. must be recognized by a specific aminoacyl-tRNA synthetase that adds the correctamino acid.D. must have an attachment site for the amino acid.E. All of these.2

Name: ______________________ID: AFigure 13-2Use the figure to answer the corresponding question(s).________8 Refer to Figure 13-2. The portion of the molecule labeled 5 is:A. the attached amino acid.B. the codon.C. a double-stranded region.D. a single-stranded region.E. the anticodon.9 The main reason scientists thought that proteins, rather than DNA, were the carriers of geneticmaterial in the cell was:A. their ability to self replicate within the cytoplasm.B. the large number of possible amino acid combinations.C. their abundance within the cell.D. their ability to be exported from the cell.E. their presence within the nucleus.3

Name: ______________________ID: A________________________10 Genes that encode proteins that are always needed are called:A. repressible genes.B. promoter genes.C. operons.D. constitutive genes.E. inducible genes.11 The codon is found in the:A. nontemplate strand of DNA.B. rRNA.C. template strand of DNA.D. mRNA.E. tRNA.12 The 3′ end of eukaryotic pre-mRNAs are changed by:A. cutting and adding 100−250 adenine nucleotides.B. removing the last phosphate group.C. phosphorylation of the mRNA molecule.D. copying the last few bases so that it can form a duplex structure.E. adding a "cap."13 In eukaryotes, some DNA sequences act as introns in some cells and as exons in other cells. Thisis an example of __________.A. gene repressionB. gene processingC. mRNA splicingD. differential mRNA processingE. gene amplification14 The first experimenters to use Griffith's transformation assay to identify the genetic material were:A. Meselson and Stahl.B. Franklin and Wilkins.C. Avery, MacLeod, and McCarty.D. Watson and Crick.E. Hershey and Chase.15 The DNA strand that is replicated smoothly and continuously is called the:A. leading strand.B. alpha strand.C. primary strand.D. lagging strand.E. first strand.4

Name: ______________________ID: A________________________16 Translational controls regulate:A. the uptake of nucleic acids into the cell.B. the attachment of phosphate groups to polypeptides.C. the rate at which an mRNA molecule is synthesized.D. the rate at which an mRNA molecule is translated.E. the activity of a protein end-product that is produced.17 RNA differs from DNA in all the following except:A. RNA is a larger molecule than DNA.B. RNA contains uracil and DNA contains thymine.C. RNA contains ribose and DNA contains deoxyribose.D. RNA is single stranded and DNA is double stranded.E. None of the above.18 In replication, once the DNA strands have been separated, reformation of the double helix isprevented by:A. DNA polymerases.B. ATP.C. DNA helicase enzyme.D. single-strand binding proteins.E. GTP.19 Retroviruses or RNA tumor viruses use __________ to make DNA.A. DNA-dependent RNA polymeraseB. reverse transcriptaseC. DNA polymeraseD. RNA polymeraseE. primase20 During protein synthesis, ribosomes:A. transcribe mRNA to tRNA.B. translate mRNA into DNA.C. attach to the mRNA molecule and travel along its length.D. translate mRNA into tRNA.E. attach to the DNA molecule and travel along its length to produce an mRNAmolecule.21 __________ determined the structure of the molecule DNA.A. FranklinB. Franklin and CrickC. Watson and CrickD. Watson, Crick, and WilkinsE. Crick and Wilkins5

Name: ______________________ID: A________________22 Initiation of transcription requires:A. an RNA primer.B. a DNA primer.C. DNA polymerase.D. a promoter sequence.E. Okazaki fragments.23 __________ used x-ray diffraction to provide images of DNA.A. Erwin ChargaffB. Frederick GriffithC. Rosalind FranklinD. Francis CrickE. James Watson24 Chargaff determined that DNA from any source contains about the same amount of guanine as__________.A. adenineB. guanineC. thymineD. uracilE. cytosine25 The focus of gene regulation in multicellular organisms is on:A. the specificity of products in different tissues.B. rapid turnover of RNA molecules.C. operons.D. economizing resources at all levels.E. All of these.6

Name: ______________________ID: AFigure 12-1Use the figure to answer the corresponding question(s).________26 The portion of the molecule in box 3 of Figure 12-1 is:A. a sugar.B. a nucleotide.C. a protein.D. a purine.E. a pyrimidine.27 The portion of the molecule in box 5 of Figure 12-1 is:A. a nucleotide.B. a protein.C. a hydrogen bond.D. a pyrimidine.E. a phosphate.7

Name: ______________________ID: AFigure 13-3Use the figure to answer the corresponding question(s).________________28 The process illustrated in Figure 13-3 is:A. transcription.B. DNA synthesis.C. a frame shift mutation.D. protein synthesis.E. translation.29 The bacteriophages used in Alfred Hershey's and Martha Chase's experiments showed that:A. proteins were responsible for the production of new viruses within the bacteria.B. proteins were injected into bacteria.C. DNA was injected into bacteria.D. DNA and protein were injected into bacteria.E. DNA remained on the outer coat of bacteria.30 Substitution of one base pair for another can result in a __________ mutation that results in theconversion of an amino acid specifying codon to a termination codon.A. nonsenseB. chromosomalC. frameshiftD. missenseE. None of these.31 Feedback inhibition of the first enzyme of a pathway by the end product of the pathway is anexample of:A. posttranslational control.B. inhibiting control.C. translational control.D. transcriptional control.E. repression.8

Name: ______________________ID: A________________________32 An inducible operon is usually controlled by:A. an inducer molecule that keeps it in the "off" state.B. being active at all times.C. allolactose.D. being turned "off," usually by the end product of the pathway.E. an active repressor that keeps it in the "off" state.33 The ends of eukaryotic chromosomes can be lengthened by:A. DNA polymerase.B. primase.C. reverse transcriptase.D. apoptosis.E. telomerase.34 Interrupted coding sequences include long sequences of bases that do not code for amino acids.These noncoding sequences, called __________, are found in __________ cells.A. exons; eukaryoticB. introns; eukaryoticC. introns; prokaryoticD. exons; prokaryoticE. None of these.35 The gene that codes for the repressor protein of the E. coli lactose operon is:A. turned off most of the time.B. downstream from the promoter region.C. downstream from the operator.D. located between the operator and the promoter.E. constitutive.36 Increasing the stability of a particular mRNA __________ the expression of that gene.A. does not affectB. increasesC. decreasesD. eliminatesE. None of these.37 Regulation of gene expression can be accomplished by controlling:A. the rate of translation of mRNA.B. the rate of mRNA degradation.C. the activity of a protein product.D. the amount of mRNA that is available.E. All of these.9

Name: ______________________ID: A________________________38 Hydrogen bonds can form between guanine and __________, and between adenine and__________.A. cytosine; thymineB. adenine; guanineC. thymine; cytosineD. phosphate; sugarE. sugar; phosphate39 Who first confirmed that the replication of DNA was semiconservative?A. Avery and GriffithB. Watson, Crick, and WilkinsC. Watson and CrickD. Meselson and StahlE. Chargaff and Hershey40 What prevents knot formation in replicating DNA?A. chromatinB. scaffolding proteinsC. histonesD. topoisomerasesE. protosomes41 An mRNA "5′ cap":A. prevents translation.B. marks the mRNA for degradation.C. facilitates binding of ribosomes.D. protects newly synthesized mRNA from degradation.E. decreases the half-life of the mRNA.42 Two chains of DNA must run in __________ direction(s) and must be __________ if they are tobond with each other.A. parallel; complementaryB. antiparallel; complementaryC. parallel; uncomplementaryD. opposite; uncomplementaryE. the same; uncomplementary43 Transformation is a process whereby:A. plasmids are transferred into viral cells.B. plasmids are transferred into bacterial cells.C. bacteria are transferred into viral cells.D. bacteria are transferred into plasmid cells.E. viruses are transferred into bacterial cells.10

Name: ______________________ID: A________________________44 DNA sequences that are methylated by a cell are usually genes that:A. are inactive.B. are repressed.C. are actively expressed.D. have been replicatedE. are constitutive.45 __________, the ends of eukaryotic chromosomes, shorten with every cell replication event.A. NucleosomesB. CentromeresC. TelomeresD. PrimosomesE. Kinetochores46 Frameshift mutations result from:A. the substitution of one base pair for another.B. the substitution of a start codon for an amino acid codon.C. the substitution of a stop codon for an amino acid-specifying codon.D. the insertion or deletion of one or two base pairs.E. the substitution of more than one base pair.47 A mutation that replaces one amino acid in a protein with another is called a __________ mutation.A. missenseB. neutralC. frameshiftD. recombinantE. nonsense48 Which of the following cause the unwinding of the DNA double helix?A. RNA primerB. DNA polymeraseC. DNA helicaseD. RNA polymeraseE. primosome49 In the experiments of Griffith, the conversion of nonlethal R-strain bacteria to lethal S-strainbacteria:A. could not be reproduced by other researchers.B. was the result of genetic mutation.C. was an example of conjugation.D. supported the case for proteins as the genetic material.E. was an example of the genetic exchange known as transformation.11

Name: ______________________ID: A________________________50 In all organisms, the AUG codon codes for:A. the initiation of translation.B. the termination of transcription.C. a termination tRNA molecule.D. the termination of chain elongation.E. the amino acid valine.51 One of the mRNA codons specifying the amino acid leucine is 5′-CUA-3′. Its correspondinganticodon is:A. 5′-GAU-3′.B. 3′-AUC-5′.C. 5′-GAT-3′.D. 3′-GAU-5′.E. 3′-GAT-5′.52 How does the lactose repressor block transcription of the lactose operon?A. by slowing the uptake of lactose into the cellB. by "turning off" the appropriate genes in the intronC. by binding allosterically to the appropriate genesD. by regulating the activity of the enzymes that the operon codes forE. by binding to the operator53 Cancer cells differ from noncancerous cells in that:A. they have the ability to resist apoptosis.B. they have elevated levels of telomerase.C. they are virtually immortal.D. they can maintain telomere length as they divide.E. All of these.54 Which of the following statements about DNA is false?A. DNA is only found in eukaryotic cells.B. DNA is capable of forming many different sequences.C. DNA contains the sugar deoxyribose.D. DNA is double-stranded rather than single-stranded.E. DNA contains thymine instead of uracil.55 Which of the following types of processing does eukaryotic mRNA undergo before it becomesfunctional?A. removal of intronsB. polyadenylationC. cappingD. splicingE. All of these.12

Name: ______________________ID: A________________________56 Which of the following adds new nucleotides to a growing DNA chain?A. DNA polymeraseB. RNA primerC. primaseD. RNA polymeraseE. DNA helicase57 The information carried by DNA is incorporated in a code specified by the:A. number of bases in a DNA strand.B. number of separate strands of DNA.C. size of a particular chromosome.D. phosphodiester bonds of the DNA strand.E. specific nucleotide sequence of the DNA molecule.58 A gene can now be defined as:A. a DNA nucleotide sequence that carries information to produce an enzyme.B. a DNA or RNA sequence that carries information to produce a specific polypeptide.C. a DNA or RNA sequence that carries information to produce a single polypeptide.D. a DNA sequence that carries information to produce a specific RNA or proteinproduct.E. a DNA nucleotide sequence that carries information to produce a specificpolypeptide.59 Bacterial gene regulation occurs mainly at the __________ level.A. transcriptionalB. feedback inhibitionC. posttranscriptionalD. translationalE. posttranslational60 A cell may meet the need for large quantities of a specific protein by:A. having multiple copies of the gene that codes for that protein.B. continuously synthesizing the mRNA molecule that specifies that protein.C. increasing the half-life of the mRNA that specifies the protein.D. All of these.E. None of these.61 Which of the following nucleotide sequences represents the complement to the DNA strand5′ − AGATCCG- 3′?A. 5′ − AGATCCG- 3′B. 3′ − CTCGAAT- 5′C. 5′ − CTCGAAT- 3′D. 3′ − AGATCCG- 5′E. 3′ − TCTAGGC- 5′13

Name: ______________________ID: A____________62 Primase is the enzyme responsible for:A. introducing nicks into the DNA double strand in order to prevent the formation ofknots.B. hydrolyzing ATP to facilitate DNA unwinding.C. forming a replication fork in the DNA double helix.D. unwinding the DNA double strand to allow DNA polymerase access to thetemplate DNA.E. making short strands of RNA at the site of replication initiation.63 Repressible genes are usually actively transcribed when:A. quantities of precursor materials are high.B. the supply of the end product formed by the enzymes encoded by these genes islow.C. tryptophan accumulates in the cell.D. repressor molecules bind to the promoter.E. there is no other substrate that can be used by the cell.64 Which of the following serves as an "adapter" in protein synthesis and bridges the gap betweenmRNA and proteins?A. promoter sequencesB. DNAC. tRNAD. rRNAE. cDNA14

ID: ADNA and Gene Expression (chaps 12-14)Answer SectionMULTIPLE CHOICE1 ANS: E2 ANS: D3 ANS: E4 ANS: E5 ANS: B6 ANS: B7 ANS: E8 ANS: A9 ANS: B10 ANS: D11 ANS: D12 ANS: A13 ANS: D14 ANS: C15 ANS: A16 ANS: D17 ANS: A18 ANS: D19 ANS: B20 ANS: C21 ANS: C22 ANS: D23 ANS: C24 ANS: E25 ANS: A26 ANS: D27 ANS: E28 ANS: A1

ID: A29 ANS: C30 ANS: A31 ANS: A32 ANS: E33 ANS: E34 ANS: B35 ANS: E36 ANS: B37 ANS: E38 ANS: A39 ANS: D40 ANS: D41 ANS: D42 ANS: B43 ANS: B44 ANS: A45 ANS: C46 ANS: D47 ANS: A48 ANS: C49 ANS: E50 ANS: A51 ANS: D52 ANS: E53 ANS: E54 ANS: A55 ANS: E56 ANS: A57 ANS: E58 ANS: D59 ANS: A60 ANS: D2

ID: A61 ANS: E62 ANS: E63 ANS: B64 ANS: CESSAY65 ANS:answers will vary3